Golf ball retrievers are well known devices generally constructed of a telescoping handle with a ball trapping or pick-up element attached to an end of the ultimate section of the handle. An exemplary form of such a retriever is shown in U.S. Pat. No. 5,265,926 of Frank L. DiNardo. The telescopic handle of such retrievers is formed of a plurality of sections and may be extendable from a collapsed length of about 3 feet to an extended length of about 18 feet. However, there are also other retrievers which may have a collapsed length of about 1 foot and extend to about 8 feet. Obviously, a 1 foot retriever extending to 8 feet requires at least eight telescoping sections.
The larger retrievers, i.e., those having an initial length of about 3 feet, generally use large diameter tubing, e.g., about 1 inch O.D. in the largest handle section, which allows use of various types of camming devices for locking the handle in any position. An exemplary form of handle structure using cam type locking devices is shown in U.S. Pat. No. 4,659,125.
While the camming structure is appropriate for larger retrievers, the smaller retrievers are generally constructed with a largest section having an outer diameter of no more than about 0.5 inch and the smallest section having an outer diameter of at least about 0.25 inch. Cam locking structures are difficult to implement in the smaller retrievers due to this reduced diameter.
Another form of handle assembly which is more practical for the smaller handles is one which relies solely on frictional engagement between the telescoping sections and does not use a positive type lock for holding the sections in a fixed position. One particular design forms each handle section with a uniform diameter except for a relatively short necked down (reduced diameter) portion at one end of each section. A pair of diametrically opposite small holes are formed at an opposite end of each section. Each inner section has an outer diameter that is less than an inner diameter of each immediately overlaying section by twice the thickness of one of a pair of bronze shims placed between the sections. Each of the shims has a punched dimple which fits into a respective one of the holes formed in the section to capture the shims in a fixed position at one end of the section. The shims form a tight, sliding relationship between adjacent sections with the bronze material acting as a bearing. Since the reduced diameter end cannot pass over the shims, the original intent was to use the shims in a secondary function to attempt to prevent the sections from being pulled apart when the retriever handle is extended.
One problem with this small handle construction is that a golfer who has to use the retriever is often angry and will attempt to extend the telescopic handle with unnecessary force. As a result, the small dimple can shear away and allow the sections to separate and destroy the retriever. This problem is exacerbated in better quality retrievers made from thin wall, stainless steel tubing since the thin wall has a near knife edge and easily shears the bronze shim material.
U.S. Pat. No. 5,908,214 discloses a further improvement in handle construction in which the pair of bronze shims are replaced by a unitary bronze sleeve extending about three quarters of the way around an end area of each telescoping tube forming the extendable handle. In the '214 patent, the shims become a one piece partial sleeve sized to fit snugly about a respective one of the telescoping tubes and having a crimped portion extending radially inward over an axial extent of the sleeve intermediate its opposite circumferential ends. Each tube has an axially extending slot adjacent a first end for receiving the crimped portion of the sleeve when the sleeve is positioned on the tube. The handle is assembled by sliding another tube over the tube and sleeve. The overlaying tube has one end terminating in a necked down portion having an inner diameter larger than an outer diameter of the inner tube and smaller than a diameter of the sleeve when the sleeve is positioned on the inner tube whereby the one end of the outer tube normally cannot pass over the sleeve on the inner tube. Unfortunately, there are occasions in which the user of the handle will jerk the extensions so hard that the shim is distorted and the smaller diameter tube will slip over the shim and cause the tubes to separate. Accordingly, it is desirable to provide an additional feature to further inhibit the tubes from separating.
U.S. Pat. No. 7,073,228, assigned to the assignee of the present invention, describes and claims a further improvement to the handle construction of the aforementioned '214 patent. As explained in the '228 patent, when the handle is extended, the weight of the several extending tubes causes the handle to deflect to a relatively large extent making the handle difficult to accurately position and put pressure on an object at the distal end of the handle. The '228 patent provides an improvement to the handle by incorporating a short stiffener at each joint of the tubes. Each of the stiffeners has an outside diameter sized to fit snugly within an inside diameter of an associated tube and is positioned in an end of the associated tube remaining within an adjacent larger diameter tube when the handle is extended. Each stiffener has an axial length at least as long as an overlap length of the associated tube and the adjacent larger diameter tube when the handle is extended. Preferrably, the stiffener includes a cap having an outside diameter substantially the same as the associated tube outside diameter to prevent the stiffener from slipping further into the end of the associated tube. Notwithstanding the greater flex strength added by the stiffeners, it is further desirable to provide a construction that will further increase the flex strength of the extended handle. It is also noted that there are instances in which the tool attached to the end of the handle can be rotated by pressure applied to the tool. For example, in the case of a golf ball retriever using a form of cup at the end of the handle for grasping a golf ball, the friction fit between each of the tube sections may allow the tubes to rotate with respect to each other such that any resistance at the retriever cup may allow it to rotate and inhibit the ability to retrieve the golf ball. Such rotation is not an issue with the longer retrievers that use a cam locking device as is described in the aforementioned '125 patent. However, with the shorter retrievers that only rely on friction fit, rotation becomes an issue.